The present invention relates to a method of forming groups of products.
The present invention may be used to advantage for forming groups of packets of cigarettes as the packets are transferred from the output of a cellophaning machine to the input of a cartoning machine, to which the following description refers purely by way of example.
On cigarette packing systems comprising a cellophaning machine connected in series with a cartoning machine, the packets of cigarettes are fed from the output of the cellophaning machine to the input of the cartoning machine via a unit for forming the packets of cigarettes into groups, and which comprises a conveying device for feeding the packets along a given path, and a compacting device located along the path and for compacting the packets into groups.
The compacting devices normally comprise either an element movable in the same direction as the packets, and which provides for compacting the packets by accelerating the last packet in each group, or a stop element for compacting the packets by decelerating or even arresting the first packet in each group. Whichever the case, once formed, the groups are fed by the conveying device to a reciprocating unloading device located at the end of the conveying device and for feeding the groups in steps to the input of the cartoning machine.
In the event the packets are arranged differently in the groups as compared with the traveling arrangement of the packets, the group forming unit also comprises an orienting device, which cooperates with the conveying device to change the orientation of the packets by turning the packets about a given axis of orientation, i.e. rotating each packet 90.degree. about a respective axis of orientation normally defined even by the longitudinal axis of the packet.
Forming the packets into groups as described above involves several drawbacks, mainly on account of the numerous devices required to form each group of packets, which not only complicates the design and increases the cost of the forming unit, but also makes the unit relatively unreliable and expensive to maintain.